Larry McGowan drives up to a marsh-ringed lake in his government-issued SUV and kills the engine before it has finished rolling to a stop. Within a few moments, a flock of Canada geese wings into view, flying low toward another flock already on the water.

Maryland’s Blackwater National Wildlife Refuge is home to one of the nation’s largest breeding populations of bald eagles and the refuge is hosting an eagle festival this weekend to celebrate the majestic birds of prey.